[Pharmwaste] Sensitive birds alert scientists to new threat
dldebiasi at deq.virginia.gov
Wed May 30 10:38:37 EDT 2007
Sensitive birds alert scientists to new threat
Sunday, May 27, 2007
ST. HELENS -- Whatever flows through the Columbia River shows up in the
ospreys that squawk and wheel above it.
The pesticide DDT, washing into the river and the fish the ospreys eat,
nearly wiped the birds out by the 1970s -- thinning their eggshells to
the breaking point. PCBs, industrial chemicals that gather in the bodies
of wildlife, also rose to dangerous levels.
The good news is those pollutants are declining, and ospreys are
The bad news is there's a new chemical appearing in ospreys, and, unlike
PCBs, it's coming from our homes. It is a flame retardant called
polybrominated diphenyl ether, or PBDE, and it's as common today as the
computers, televisions and furniture that contain it.
PBDEs appear to be rinsing out of homes and businesses in sewage,
through treatment plants and into rivers, where they end up in fish and
the birds that eat them, scientists say.
That makes the birds a telling barometer not only of what's in the
river, but also what is in us -- because we're exposed, too.
Young salmon from the Willamette River near the Morrison Bridge contain
concentrations of the flame retardants known to cause neurological
damage in laboratory rats, according to new studies by the National
Marine Fisheries Service. The levels were twice as high as in salmon
from Seattle Harbor, possibly because the Willamette funnels chemicals
U.S. Geological Survey scientists began tracking chemicals in Columbia
River osprey more than 10 years ago. Now they're looking for this new
Branden Johnson, a Corvallis-based biologist with the U.S. Geological
Survey, climbs an extension ladder propped on the deck of a boat as two
irritated ospreys circle overhead. She plucks an egg from their
3-foot-wide nest atop a weather-beaten piling west of St. Helens.
Taking the egg will scarcely dent the osprey population, since one chick
in a nest often dies regardless. But its contents will give scientists a
snapshot of toxins building in the birds.
The studies are a combination of painstaking data-crunching and
on-the-water bravery. As wind whips up waves near the mouth of the
Columbia estuary, biologist James Kaiser leaps from the ladder on a
channel marker back to the bobbing boat -- egg nestled in a padded
section of PVC pipe.
Biologists credit some of the osprey's resurgence to the U.S. Coast
Guard, which gave up trying to keep the birds from nesting on channel
markers. Instead, the Coast Guard began adding platforms so they could
nest without blocking lights that guide ship traffic.
"The Coast Guard accommodated them instead of trying to do battle with
them," Kaiser said.
Scientists keep careful notes on the number of eggs in each nest and how
long the birds are off the nests as eggs are retrieved. A laboratory in
coming months will check levels of PBDEs in the eggs.
The flame retardants are chemically similar to PCBs and on their way to
becoming a modern-day version of PCBs. Although PBDEs have generally not
yet reached levels that threaten bird reproduction, like PCBs, they
build over time.
Other studies have found levels doubling in some wildlife every three to
five years, said Barnett Rattner, a research scientist at the Geological
Survey's Patuxent Wildlife Research Center.
"If it keeps doubling, in five or 10 years, we might" reach harmful
levels, he said.
PBDEs have been found in household dust and breast milk of Northwest
mothers, and levels are rising in people, too. But the compounds have
gained attention so recently it's still not clear how much is too much.
Washington state last month restricted flame retardants in certain new
products, such as mattresses -- overriding intense lobbying by the
chemical industry. Other states are considering similar moves. Oregon
banned two types of retardants but not the third outlawed in Washington.
The problem is that even with the bans, a vast storehouse of the
compounds remains in products, such as plastic television housings,
already in use.
"This is something we come into contact with on a daily basis, in our
homes and in our work," said Michael Ikonomou, a research scientist at
Fisheries and Oceans Canada, who in 2003 found that flame-retardant
levels in mountain whitefish near the Columbia River headwaters had
doubled in less than two years.
Osprey wield tiny spines on their talons to help snatch fish from the
water and depend on fish for almost all their food. An osprey pair
consumes about 375 pounds of fish during the breeding season.
Osprey eggs along the lowest stretch of the Columbia River, from St.
Helens west, and part of the Yakima River had the highest levels of PBDE
in testing from 2002 to 2004. That may be connected to PBDE-laden
wastewater entering the rivers nearby and to where in the river the
compounds tend to settle out.
The same section of the Columbia is the only place the number of osprey
young per nest declined from 1997 to 2004, even as the total number of
nests increased. It's not clear why -- though eagles, which steal fish
from osprey, may have a role. Mate for life
PBDE levels were lowest in osprey eggs from the more remote headwaters
of the Willamette River.
Ospreys mate for life, winter in Mexico and Central America, and return
to the same nest each spring.
The emergence of PBDEs is a mirror opposite of the decline of DDT and
PCBs, which were widely banned in the 1970s. They built up in wildlife
and the environment and took decades to start declining.
Through the late 1990s some osprey eggs from the Columbia contained high
levels of DDE, a byproduct of DDT. Their eggshells thinned by nearly 20
percent, and fewer hatchlings survived.
But the DDE levels dropped sharply by the time of repeat testing in
2004. Total PCB concentrations in eggs dropped roughly by half over the
same period, according to Geological Survey studies led by Charles
Henny, a research zoologist in Corvallis.
On the other hand, mercury levels rose about 50 percent, though they
remain below levels known to be toxic to wildlife.
Osprey numbers responded to reduced loads of PCBs and DDE, zooming from
13 pairs on the Willamette between Portland and Eugene in the 1970s to
more than 250 today. The number on the Columbia from Umatilla west
jumped from 94 in 1997 to 225 in 2004.
"They've finally been released from the reproductive injury of those
traditional chemicals," said Bob Grove, a scientist on Henny's team.
"It's taken this long for the environment to clean it up."
Michael Milstein: 503-294-7689; michaelmilstein@ news.oregonian.com
(c)2007 The Oregonian
Deborah L. DeBiasi
Email: dldebiasi at deq.virginia.gov
WEB site address: www.deq.virginia.gov
Virginia Department of Environmental Quality
Office of Water Permit Programs
Industrial Pretreatment/Toxics Management Program
Mail: P.O. Box 1105, Richmond, VA 23218 (NEW!)
Location: 629 E. Main Street, Richmond, VA 23219
More information about the Pharmwaste